In the bowl of a stand mixer, cream together the butter and sugar until light yellow. Beat in vanilla, eggs, and peanut butter on low speed until everything is combined.

In a small bowl, sift together the flour, baking powder, and salt. Slowly add the flour mixture to the peanut butter mixture. Mix just until combined.

Spread half of the dough in the bottom of the prepared pan. Spread jam evenly over the top of the dough. Use your hands to make large balls of dough with the remaining half of dough, then flatten them out and place them over the jam. The dough will spread a bit in the oven, so it’s okay if there are bare spots. Sprinkle with the chopped peanuts and bake for 45 minutes.